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diff --git a/man/SD_JOURNAL_FOREACH.html b/man/SD_JOURNAL_FOREACH.html deleted file mode 100644 index 191e9db582..0000000000 --- a/man/SD_JOURNAL_FOREACH.html +++ /dev/null @@ -1,93 +0,0 @@ -<html><head><meta http-equiv="Content-Type" content="text/html; charset=UTF-8"><title>sd_journal_next</title><meta name="generator" content="DocBook XSL Stylesheets V1.78.1"></head><body bgcolor="white" text="black" link="#0000FF" vlink="#840084" alink="#0000FF"><style> - a.headerlink { - color: #c60f0f; - font-size: 0.8em; - padding: 0 4px 0 4px; - text-decoration: none; - visibility: hidden; - } - - a.headerlink:hover { - background-color: #c60f0f; - color: white; - } - - h1:hover > a.headerlink, h2:hover > a.headerlink, h3:hover > a.headerlink, dt:hover > a.headerlink { - visibility: visible; - } - </style><a href="index.html">Index </a>· - <a href="systemd.directives.html">Directives </a>· - <a href="../python-systemd/index.html">Python </a>· - - <span style="float:right">systemd 221</span><hr><div class="refentry"><a name="sd_journal_next"></a><div class="titlepage"></div><div class="refnamediv"><h2>Name</h2><p>sd_journal_next, sd_journal_previous, sd_journal_next_skip, sd_journal_previous_skip, SD_JOURNAL_FOREACH, SD_JOURNAL_FOREACH_BACKWARDS — Advance or set back the read pointer in the journal</p></div><div class="refsynopsisdiv"><h2>Synopsis</h2><div class="funcsynopsis"><pre class="funcsynopsisinfo">#include <systemd/sd-journal.h></pre><table border="0" class="funcprototype-table" summary="Function synopsis" style="cellspacing: 0; cellpadding: 0;"><tr><td><code class="funcdef">int <b class="fsfunc">sd_journal_next</b>(</code></td><td>sd_journal *<var class="pdparam">j</var><code>)</code>;</td></tr></table><div class="funcprototype-spacer"> </div><table border="0" class="funcprototype-table" summary="Function synopsis" style="cellspacing: 0; cellpadding: 0;"><tr><td><code class="funcdef">int <b class="fsfunc">sd_journal_previous</b>(</code></td><td>sd_journal *<var class="pdparam">j</var><code>)</code>;</td></tr></table><div class="funcprototype-spacer"> </div><table border="0" class="funcprototype-table" summary="Function synopsis" style="cellspacing: 0; cellpadding: 0;"><tr><td><code class="funcdef">int <b class="fsfunc">sd_journal_next_skip</b>(</code></td><td>sd_journal *<var class="pdparam">j</var>, </td></tr><tr><td> </td><td>uint64_t <var class="pdparam">skip</var><code>)</code>;</td></tr></table><div class="funcprototype-spacer"> </div><table border="0" class="funcprototype-table" summary="Function synopsis" style="cellspacing: 0; cellpadding: 0;"><tr><td><code class="funcdef">int <b class="fsfunc">sd_journal_previous_skip</b>(</code></td><td>sd_journal *<var class="pdparam">j</var>, </td></tr><tr><td> </td><td>uint64_t <var class="pdparam">skip</var><code>)</code>;</td></tr></table><div class="funcprototype-spacer"> </div><table border="0" class="funcprototype-table" summary="Function synopsis" style="cellspacing: 0; cellpadding: 0;"><tr><td><code class="funcdef"><b class="fsfunc">SD_JOURNAL_FOREACH</b>(</code></td><td>sd_journal *<var class="pdparam">j</var><code>)</code>;</td></tr></table><div class="funcprototype-spacer"> </div><table border="0" class="funcprototype-table" summary="Function synopsis" style="cellspacing: 0; cellpadding: 0;"><tr><td><code class="funcdef"><b class="fsfunc">SD_JOURNAL_FOREACH_BACKWARDS</b>(</code></td><td>sd_journal *<var class="pdparam">j</var><code>)</code>;</td></tr></table><div class="funcprototype-spacer"> </div></div></div><div class="refsect1"><a name="idm47952643779984"></a><h2 id="Description">Description<a class="headerlink" title="Permalink to this headline" href="#Description">¶</a></h2><p><code class="function">sd_journal_next()</code> advances the read - pointer into the journal by one entry. The only argument taken is - a journal context object as allocated via - <a href="sd_journal_open.html"><span class="citerefentry"><span class="refentrytitle">sd_journal_open</span>(3)</span></a>. - After successful invocation the entry may be read with functions - such as - <a href="sd_journal_get_data.html"><span class="citerefentry"><span class="refentrytitle">sd_journal_get_data</span>(3)</span></a>.</p><p>Similarly, <code class="function">sd_journal_previous()</code> sets - the read pointer back one entry.</p><p><code class="function">sd_journal_next_skip()</code> and - <code class="function">sd_journal_previous_skip()</code> advance/set back - the read pointer by multiple entries at once, as specified in the - <code class="varname">skip</code> parameter.</p><p>The journal is strictly ordered by reception time, and hence - advancing to the next entry guarantees that the entry then - pointing to is later in time than then previous one, or has the - same timestamp.</p><p>Note that - <a href="sd_journal_get_data.html"><span class="citerefentry"><span class="refentrytitle">sd_journal_get_data</span>(3)</span></a> - and related calls will fail unless - <code class="function">sd_journal_next()</code> has been invoked at least - once in order to position the read pointer on a journal - entry.</p><p>Note that the <code class="function">SD_JOURNAL_FOREACH()</code> - macro may be used as a wrapper around - <a href="sd_journal_seek_head.html"><span class="citerefentry"><span class="refentrytitle">sd_journal_seek_head</span>(3)</span></a> - and <code class="function">sd_journal_next()</code> in order to make - iterating through the journal easier. See below for an example. - Similarly, <code class="function">SD_JOURNAL_FOREACH_BACKWARDS()</code> may - be used for iterating the journal in reverse order.</p></div><div class="refsect1"><a name="idm47952643768000"></a><h2 id="Return Value">Return Value<a class="headerlink" title="Permalink to this headline" href="#Return%20Value">¶</a></h2><p>The four calls return the number of entries advanced/set - back on success or a negative errno-style error code. When the end - or beginning of the journal is reached, a number smaller than - requested is returned. More specifically, if - <code class="function">sd_journal_next()</code> or - <code class="function">sd_journal_previous()</code> reach the end/beginning - of the journal they will return 0, instead of 1 when they are - successful. This should be considered an EOF marker.</p></div><div class="refsect1"><a name="idm47952643765184"></a><h2 id="Notes">Notes<a class="headerlink" title="Permalink to this headline" href="#Notes">¶</a></h2><p>The <code class="function">sd_journal_next()</code>, - <code class="function">sd_journal_previous()</code>, - <code class="function">sd_journal_next_skip()</code> and - <code class="function">sd_journal_previous_skip()</code> interfaces are - available as a shared library, which can be compiled and linked to - with the - <code class="constant">libsystemd</code> <a href="http://linux.die.net/man/1/pkg-config"><span class="citerefentry"><span class="refentrytitle">pkg-config</span>(1)</span></a> - file.</p></div><div class="refsect1"><a name="idm47952643760016"></a><h2 id="Examples">Examples<a class="headerlink" title="Permalink to this headline" href="#Examples">¶</a></h2><p>Iterating through the journal:</p><pre class="programlisting">#include <stdio.h> -#include <string.h> -#include <systemd/sd-journal.h> - -int main(int argc, char *argv[]) { - int r; - sd_journal *j; - r = sd_journal_open(&j, SD_JOURNAL_LOCAL_ONLY); - if (r < 0) { - fprintf(stderr, "Failed to open journal: %s\n", strerror(-r)); - return 1; - } - SD_JOURNAL_FOREACH(j) { - const char *d; - size_t l; - - r = sd_journal_get_data(j, "MESSAGE", (const void **)&d, &l); - if (r < 0) { - fprintf(stderr, "Failed to read message field: %s\n", strerror(-r)); - continue; - } - - printf("%.*s\n", (int) l, d); - } - sd_journal_close(j); - return 0; -}</pre></div><div class="refsect1"><a name="idm47952643757392"></a><h2 id="See Also">See Also<a class="headerlink" title="Permalink to this headline" href="#See%20Also">¶</a></h2><p> - <a href="systemd.html"><span class="citerefentry"><span class="refentrytitle">systemd</span>(1)</span></a>, - <a href="sd-journal.html"><span class="citerefentry"><span class="refentrytitle">sd-journal</span>(3)</span></a>, - <a href="sd_journal_open.html"><span class="citerefentry"><span class="refentrytitle">sd_journal_open</span>(3)</span></a>, - <a href="sd_journal_get_data.html"><span class="citerefentry"><span class="refentrytitle">sd_journal_get_data</span>(3)</span></a>, - <a href="sd_journal_get_realtime_usec.html"><span class="citerefentry"><span class="refentrytitle">sd_journal_get_realtime_usec</span>(3)</span></a>, - <a href="sd_journal_get_cursor.html"><span class="citerefentry"><span class="refentrytitle">sd_journal_get_cursor</span>(3)</span></a> - </p></div></div></body></html> |